There is a lot of debate about this. Some would argue that if there are a lot of graduates that many will be "forced" into commercial practices, hence the downfall of optometry. You'll forgive me if I cry you guys a river about being forced to go into a job making $100K as a starting salary. You can be a good OD anywhere if you choose to.
My opinion is that there will be plenty of jobs, but you will have to be more selective about where you choose to practice. Optometry is having to deal with the same market forces that most businesses have to deal with...supply and demand. Optometry is no longer a field that any bozo can go into and make a million dollars anywhere they like. You have to do your homework and find not only attractive places to live, but attractive places to PRACTICE. They are not always the same thing. I enjoyed Memphis, but I didn't want to practice in a city with 200 ODs and an OD school seeing 50,000 patients per year.
With regard to ophthalmology, it's a good profession as well but the practice dynamics are different. You are in a different type of practice revolving around surgery and advanced secondary care. To be honest, I probably make as much as a middle of the road ophthalmologist and have a better job...not as exciting, not as highly regarded, but at the end of the day I go home. No real afterhours call, no 6AM surgery, when I want to go on vacation it's not a big deal, no ER rotations. It's a better life in my opinion, but I'm not ruled by my ego and I enjoy the type of patient interaction I'm able to have.